However, depending on what you need to do with it, here are the standard procedures for handling such files:
: If the repair fails, you can try extracting with the "Keep broken files" checkbox ticked in WinRAR's advanced extraction settings to salvage what is usable. A.Plague.Tale.Requiem-GOG.part11.rar
If you are getting an "Unexpected end of archive" or "Checksum error" specifically pointing to part 11, the file is likely damaged. However, depending on what you need to do
Click the (next to "Play") -> Manage installation -> Verify / Repair . : If part11 is missing or permanently corrupted,
: If part11 is missing or permanently corrupted, you must re-download that specific part. GOG installers often consist of many small parts to make resuming failed downloads easier. 3. GOG Galaxy Verification
The client will check your local files and automatically download any missing or corrupted data. My game data is corrupt. How can I repair my game?
: Open part11.rar in WinRAR, go to Tools , and select Repair archive . WinRAR will attempt to create a "fixed" version of that specific part.